“…I contemplate with sovereign reverence that act of the whole American people which declared that their legislature should "make no law respecting an establishment of religion, or prohibiting the free exercise thereof," thus building a wall of separation between Church & State…”

"Question with boldness even the existence of God; because, if there be one, he must more approve of the homage of reason than that of blindfolded fear."

"Atheism is more than just the knowledge that gods do not exist, and that religion is either a mistake or a fraud. Atheism is an attitude, a frame of mind that looks at the world objectively, fearlessly, always trying to understand all things as a part of nature." Carl Sagan

"When I was a kid I used to pray every night for a new bicycle. Then I realised that the Lord doesn't work that way so I stole one and asked Him to forgive me.""The invisible and the non-existent look very much alike.""Extraordinary claims require extraordinary evidence."

Live a good life. If there are gods and they are just, then they will not care how devout you have been, but will welcome you based on the virtues you have lived by. If there are gods, but unjust, then you should not want to worship them. If there are no gods, then you will be gone, but will have lived a noble life that will live on in the memories of your loved ones.

“That which can be asserted without evidence, can be dismissed without evidence.” Christopher Hitchens.

“Those who can make you believe absurdities, can make you commit atrocities.” Voltaire.

“The Bible has noble poetry in it... and some good morals and a wealth of obscenity, and upwards of a thousand lies.” Mark Twain.

“Scientists do not join hands every Sunday and sing "Yes gravity is real! I know gravity is real! I will have faith! I believe in my heart that what goes up, up, up must come down, down, down. Amen!" If they did, we would think they were pretty insecure about the concept.” Dan Barker.

“If there is a God, atheism must seem to Him as less of an insult than religion.” Edmond De Goncourt.

“With or without religion, you would have good people doing good things and evil people doing evil things. But for good people to do evil things, that takes religion.” Steven Weinberg.

“A preoccupation with the next world clearly shows an inability to cope credibly with this one.” Richard K. Morgan.

“I try to deny myself any illusions or delusions, and I think that this perhaps entitles me to try and deny the same to others, at least as long as they refuse to keep their fantasies to themselves.” Christopher Hitchens.

“People wrap themselves in their beliefs. And they do it in such a way that you can't set them free. Not even the truth will set them free.” Michael Specter.

“What is wrong with inciting intense dislike of a religion if the activities or teachings of that religion are so outrageous, irrational or abusive of human rights that they deserve to be intensely disliked?” Rowan Atkinson.

And my all time favorite:

"Is God willing to prevent evil, but not able? Then he is not omnipotent. Is he able, but not willing? Then he is malevolent. Is he both able and willing? Then whence cometh evil? Is he neither able nor willing? Then why call him God?" Epicurus.

Anthony, I like those and have saved them, but there's one I've not hear before that very much impressed me:

“Scientists do not join hands every Sunday and sing "Yes gravity is real! I know gravity is real! I will have faith! I believe in my heart that what goes up, up, up must come down, down, down. Amen!" If they did, we would think they were pretty insecure about the concept.” Dan Barker.

This one does not belong here since it was uttered by a Unitarian minister, not an atheist. However Unitarians are not that far from atheists (a mathematician friend once defined Unitarians as "people who believe there is at most one god"). Furthermore the quote is apt and accurate. It comes from F. Forrester Church, III, the son of Senator Frank Church.